ORIGINAL ARTICLE Effect of microencapsulation and mango peel powder on probiotics survival in ice cream Efeito da microencapsulação e pó de casca de manga na sobrevivȇncia de probióticos em sorvete María Hayayumi-Valdivia1* , Luis Francisco Márquez-Villacorta1, Carla Consuelo Pretell-Vásquez1 1Universidad Privada Antenor Orrego, Facultad de Ciencias Agrarias, Escuela de Ingeniería en Industrias Alimentarias, Trujillo, La Libertad - Peru *Corresponding Author: María Hayayumi-Valdivia, Universidad Privada Antenor Orrego, Facultad de Ciencias Agrarias, Escuela de Ingeniería en Industrias Alimentarias, Avenida América Sur, 3145, Urbanización Monserrate, La Libertad, 51, Trujillo - Peru, e-mail: [email protected] Cite as: Hayayumi-Valdivia, M., Márquez-Villacorta, L. F., & Pretell-Vásquez, C. C. (2021). Effect of microencapsulation and mango peel powder on probiotics survival in ice cream. Brazilian Journal of Food Technology, 24, e2019309. https://doi.org/10.1590/1981-6723.30919 Abstract This study evaluated the effect of microencapsulation and addition of mango peel powder on the survival of Lactobacillus acidophilus and Bifidobacterium lactis, overrun, apparent viscosity, and overall acceptability of symbiotic ice cream during storage at -20 °C for 180 days. Six formulations of vanilla-flavored ice cream were prepared: three with addition of probiotic cultures at a concentration of 108 CFU/g and 0, 2%, and 3% mango peel powder microencapsulated in a sodium alginate matrix, and three with free addition. Analytical evaluations were performed after 1, 30, 60, 90, 120 and 180 days of storage. The results showed that microencapsulation of probiotics and prebiotics statistically influenced (p < 0.05) the characteristics evaluated. The formulation with microencapsulated probiotics and 2% mango peel powder was considered as the best product. This formulation is promising for future commercial application as a functional food because, at the end 180 days of storage, it showed probiotics population >106 CFU/g, 72.97% overrun, 292 mPA apparent viscosity, and good overall acceptance (7.6 points) equivalent to “I like it very much”. Keywords: Co-encapsulation; Symbiotic; Probiotics; Lactobacillus acidophilus; Bifidobacterium lactis; Ice cream; Mango peel; By-products. Resumo O efeito da microencapsulação e da adição de casca de manga em pó na sobrevivência de Lactobacillus acidophilus e Bifidobacterium lactis, overrun, viscosidade aparente e aceitabilidade geral de sorvete simbiótico durante o armazenamento a -20 °C por 180 dias foram avaliados. Foram elaboradas seis formulações de sorvete com sabor de baunilha, dentre as quais três foram adicionadas com culturas probióticas em uma concentração de 108 CFU/g e casca de manga em pó em 0, 2% e 3% microencapsuladas em uma matriz de alginato de sódio e as outras três foram adicionadas livremente. Foram realizadas avaliações analíticas em 1, 30, 60, 90, 120 e 180 dias de This is an Open Access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. Braz. J. Food Technol., Campinas, v. 24, e2019309, 2021 | https://doi.org/10.1590/1981-6723.30919 1/9 Effect of microencapsulation and mango peel powder on probiotics survival in ice cream Hayayumi Valdivia, M. L. et al. armazenamento. Os resultados mostraram que a microencapsulação de probióticos e prebióticos influenciaram estatisticamente (p < 0,05) os parâmetros avaliados. A formulação com probióticos microencapsulados e 2% de casca de manga em pó foi considerada como o melhor produto com uma futura aplicação comercial como alimento funcional, pois, aos 180 dias de armazenamento mantinha a população probiótica acima de 106 UFC/g, 72,97% de overrun, 292 mPA de viscosidade aparente e obteve uma boa aceitação geral (média de 7,6 pontos). Palavras-chave: Co-encapsulamento; Simbiótico; Probióticos; L. acidophilus; B. lactis; Sorvete; Casca de manga; Subprodutos. 1 Introduction Probiotics are defined as “live microorganisms that, when administered in adequate amounts, confer a health benefit on the host” (Hill et al., 2014). For sustaining positive effects in humans, the probiotic carrier must contain a high quantity of probioactives and maintain sufficient viable numbers (106 to 107 CFU/g of carrier food product) at the time of consumption (Guarner et al., 2017; Champagne et al., 2018; Ranadheera et al., 2018). Prebiotics are substrates that beneficially affect host organisms by selectively stimulating the growth and/or activity of populations of bacteria in the gut. Currently established prebiotics are carbohydrate-based, but other substances such as polyphenols and polyunsaturated fatty acids converted to respective conjugated fatty acids might fit the updated definition, assuming a convincing weight of evidence in the target host (Gibson et al., 2017). The processing of fruits, such as mango, generates a large number of agro-industrial by-products, which are mostly disposed in landfills and used in animal feed, but that could be used as prebiotics (Serrano-Casas et al., 2017) due to their dietary fiber content and antioxidant components (Serna Cock & Torres León, 2015; Pacheco, 2015). The dairy industry has found in probiotics a tool for the development of new functional products, with Lactobacillus and Bifidobacterium the most used strains (Cruz et al., 2009). Several studies have demonstrated the potential of ice cream as a vehicle for the inclusion of these beneficial microorganisms in the human diet (Balthazar et al., 2017; Kalicka et al., 2019; Araújo et al., 2012; Abghari et al., 2011), reporting a product with good acceptance and counts of probiotics >106 CFU/g at the end of shelf life. Dietary fiber from fruit processing residues has been investigated as a texturizing, stabilizing and emulsifying agent that generates a desirable effect on the physical, chemical and sensory properties of ice cream (Akalın et al., 2018; Ayar et al., 2018). Microencapsulation has been used to protect probiotic bacteria from the reaction with other compounds and maintain their viability during processing, storage, and along the gastrointestinal tract (Martín et al., 2015; Caicedo, 2010). Other compounds can be added to improve the stability of the capsules and the viability of microencapsulated microorganisms (Pradeep Prasanna & Charalampopoulos, 2019; Peredo, 2014). The present study evaluated the effect of microencapsulation and addition of mango peel powder on the survival of probiotics as an alternative to obtain sensory acceptable ice cream with beneficial characteristics for health. 2 Materials and methods 2.1 Preparation of mango peel powder The method described by Jibaja Espinoza (2014) was followed. Peels of ripe mangoes were collected from juice processing stalls in the municipality of Trujillo, Peru. They were washed and disinfected with a 100 ppm chlorine dioxide solution. Moisture excess was removed from the peels and they were then cut into rectangles Braz. J. Food Technol., Campinas, v. 24, e2019309, 2021 | https://doi.org/10.1590/1981-6723.30919 2/9 Effect of microencapsulation and mango peel powder on probiotics survival in ice cream Hayayumi Valdivia, M. L. et al. approximately 2 cm wide and 3 cm long. After that, they were placed in a forced-air dehydrator at 55 °C for 6 h until moisture content ≤ 10% was reached. Finally, using a hammer mill (F-180, China), they were reduced in size and then sifted through a Tyler no. 120 mesh (125 um). 2.2 Activation of probiotic cultures Lyophilized cultures of Lactobacillus acidophilus (Centro Sperimentale del Latte, Italy) and Bifidobacterium lactis (Centro Sperimentale del Latte, Italy) were inoculated separately in glass tubes containing De Man Rogosa Sharpe (MRS) broth in 1:10 ratio and incubated at 37 °C for 24 h under aerobic conditions. Then they were centrifuged at 4000 rpm at 4 °C for 10 min, washed twice with 0.9% sterile saline under the same centrifugation conditions; the resulting pellet was diluted in 2 mL of 0.9% sterile saline (10-1 dilution) (Khosravi Zanjani et al., 2014). The counts of L. acidophilus and B. lactis in the suspensions were enumerated by plate count on MRS agar. For L. acidophilus count, the spread plate method in MRS was used, whereas for B. Lactis count, the poured plate method with MRS agar supplemented with 0.5% of a 10% cysteine solution, 0.5% of 10 mg/100 mL dicloxacycline, and 1% of a solution of 10% lithium chloride (Homayouni et al., 2008). Both were incubated under anaerobic conditions at 37 °C for 72 h and the cell concentration was expressed as CFU/mL of suspension. 2.3 Microencapsulation procedure The activated cultures and the mango peel powder at 0, 2%, or 3% w/v were added to a 1% w/w sodium alginate solution. For formation of the microcapsules, the mixture was passed through a sterile syringe with a 21 G needle and dropped from the height of 30 cm into a 2.5% calcium chloride solution under constant stirring (Karthikeyan et al., 2014). The formed microcapsules were kept in the solution for 35 min until hardening was achieved and subsequently separated and washed with distilled water (Jurkiewicz et al., 2011). The counts of probiotics were performed by diluting 1 g of microcapsules in 100 mL phosphate buffer to obtain a 10-2 dilution. Then the same counting methods mentioned in the activation of probiotics cultures were used, but the cell concentration was expressed as CFU/g of microcapsules. 2.4 Ice cream manufacture The base mix for the ice cream had the following ingredients: UHT whole milk (Gloria, Peru), 36% fat pasteurized milk cream (Gloria, Peru), granulated white sugar (Laredo, Peru), caboxymethyl cellulose (Dynacell, Unitech, China), emulsifier (Ludafa, Peru), vanilla essence (Pima, Peru), skim milk powder, and glucose. For manufacturing the vanilla-flavored ice cream, the whole milk (68.35%) was heated together with the milk cream (13%) at 50 °C and then the skim milk powder (3%), sugar (12%), glucose (2.8%), carboxymethyl cellulose (0.20%), emulsifier (0.35%) and vanilla (0.30%) were added.